with the holes for the wheels all cut
out, as well as the other parts that
make up the drive unit. The robot
will be four wheel drive with a
motor and gear box in each corner
(that was extracted from an 18 volt
Dewalt cordless drill). You can see
the guts from two of the drills (in
Figure 2) with blue painters tape
over the motors to keep stray bits of
metal from getting sucked inside
and onto the magnets.

For tires, I used four wheels
that were originally meant to be
caster wheels on some type of
cart. They were very grippy,
relatively light weight, and came
with a bore already set up with a
key way to transfer the drive power
from the half inch drive shaft to
the tire.

Since the bright yellow cases
that the drills came in didn’t offer
an easy way to mount them in a
robot, I got rid of them. Instead, I
used an aluminum mount from
Teamdelta.com combined with a
clear mount that I made from
polycarbonate to attach the motors
to the aluminum drive pods. In
Figure 3, you can see the motor
with the mounts, the bronze
bushings I used for drive bearings,
and the half inch drive shaft with
a funky (and obviously male!)

FIGURE 5

FIGURE 3

spline that fits into the female
spline-shaped output that the
Dewalt drill motors have.

I was trying to cram a lot of
robot into 60 pounds, and I knew
early on it was going to be tight on
weight. Figure 4 shows the two
drive pods after I basically turned
them into Swiss cheese! It takes a
lot of holes in quarter inch thick
aluminum to lose any weight. (For
example, it takes 135 holes that are
5/8” diameter to lose one pound!)
Also in Figure 4 you can see the
first parts of the steel frame that
connect the two drive pods
together, bolted to the aluminum
drive pods (and like the drive pods,
they are also full of holes!).

You can see the robot starting
to take shape in Figure 5; when you
look at it from the side it resembles
a parallelogram. The majority of the
robots that fight in robot combat
rely on some type of heavy blade
that spins at 2. 4 billion miles per
hour to build up a bunch of kinetic
energy, and then they hit your robot
with said blade usually ripping large
chunks of it off. To combat these
spinners, I hoped to use the angled
front and back ends of the robot to
deflect any hits from these
monsters.

Figure 6 really shows the robot

FIGURE 6

FIGURE 4

coming together. I used 1/8 inch
thick by 3/4 inch wide cold rolled
steel strapping Mig welded together
to build most of the frame. I drilled
lots of holes in some of the frame
members and left some of them
solid, depending on how much
force I anticipated each piece would
see in combat. I personally don’t
like looking at metal boxes fighting
each other, so I tried really hard to
put lots of interesting angles into
Hot Stuff.

I struggled for a while to find
a small enough fuel tank to power
the flame thrower since most of
the tanks I found where meant for
portable torches used in plumbing.
These tanks were both too large
and too heavy. I settled on a butane
fuel tank and valve from a camping
stove to power the flame thrower on
Hot Stuff. I cut the rubber tubing
from the camping burner and
plumbed it to a 24 volt solenoid
valve that I could turn on and off
by remote control. I used another
length of tubing to run from the
solenoid valve to the front of the
lifting arm so the flame would come
out there. To ignite the gas, I used
an electronic sparking unit meant
for a cooking BBQ that turns on
whenever the gas valve opens
(see Figure 7).